debug/pcprofiledump.c

   1 /* Dump information generated by PC profiling.
   2    Copyright (C) 1999-2025 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 /* This is mainly an example.  It shows how programs which want to use
  20    the information should read the file.  */
  21 #ifdef HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include <argp.h>
  26 #include <byteswap.h>
  27 #include <errno.h>
  28 #include <error.h>
  29 #include <fcntl.h>
  30 #include <inttypes.h>
  31 #include <libintl.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <unistd.h>
  35 #include <stdint.h>
  36
  37 #include "../version.h"
  38
  39 #define PACKAGE _libc_intl_domainname
  40
  41 #ifndef _
  42 # define _(Str) gettext (Str)
  43 #endif
  44
  45 #ifndef N_
  46 # define N_(Str) Str
  47 #endif
  48
  49 /* Definitions of arguments for argp functions.  */
  50 static const struct argp_option options[] =
  51 {
  52   { "unbuffered", 'u', NULL, 0, N_("Don't buffer output") },
  53   { NULL, 0, NULL, 0, NULL }
  54 };
  55
  56 /* Short description of program.  */
  57 static const char doc[] = N_("Dump information generated by PC profiling.");
  58
  59 /* Strings for arguments in help texts.  */
  60 static const char args_doc[] = N_("[FILE]");
  61
  62 /* Function to print some extra text in the help message.  */
  63 static char *more_help (int key, const char *text, void *input);
  64
  65 /* Prototype for option handler.  */
  66 static error_t parse_opt (int key, char *arg, struct argp_state *state);
  67
  68 /* Name and version of program.  */
  69 static void print_version (FILE *stream, struct argp_state *state);
  70 void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
  71
  72 /* Data structure to communicate with argp functions.  */
  73 static struct argp argp =
  74 {
  75   options, parse_opt, args_doc, doc, NULL, more_help
  76 };
  77
  78 /* Try to read SIZE bytes from FD and store them on BUF.  Terminate
  79    the process upon read error.  Also terminate the process if less
  80    than SIZE bytes are remaining in the file.  If !IN_HEADER, do not
  81    terminate the process if the end of the file is encountered
  82    immediately, before any bytes are read.
  83
  84    Returns true if SIZE bytes have been read, and false if no bytes
  85    have been read due to an end-of-file condition.  */
  86 static bool
  87 read_exactly (int fd, void *buffer, size_t size, bool in_header)
  88 {
  89   char *p = buffer;
  90   char *end = p + size;
  91   while (p < end)
  92     {
  93       ssize_t ret = TEMP_FAILURE_RETRY (read (fd, p, end - p));
  94       if (ret < 0)
  95         {
  96           if (in_header)
  97             error (EXIT_FAILURE, errno, _("cannot read header"));
  98           else
  99             error (EXIT_FAILURE, errno,  _("cannot read pointer pair"));
 100         }
 101       if (ret == 0)
 102         {
 103           if (p == buffer && !in_header)
 104             /* Nothing has been read.  */
 105             return false;
 106           if (in_header)
 107             error (EXIT_FAILURE, 0, _("unexpected end of file in header"));
 108           else
 109             error (EXIT_FAILURE, 0,
 110                    _("unexpected end of file in pointer pair"));
 111         }
 112       p += ret;
 113     }
 114   return true;
 115 }
 116
 117 int
 118 main (int argc, char *argv[])
 119 {
 120   /* Set locale via LC_ALL.  */
 121   setlocale (LC_ALL, "");
 122
 123   /* Set the text message domain.  */
 124   textdomain (PACKAGE);
 125
 126   /* Parse and process arguments.  */
 127   int remaining;
 128   argp_parse (&argp, argc, argv, 0, &remaining, NULL);
 129
 130   int fd;
 131   if (remaining == argc)
 132     fd = STDIN_FILENO;
 133   else if (remaining + 1 != argc)
 134     {
 135       argp_help (&argp, stdout, ARGP_HELP_SEE | ARGP_HELP_EXIT_ERR,
 136                  program_invocation_short_name);
 137       exit (1);
 138     }
 139   else
 140     {
 141       /* Open the given file.  */
 142       fd = open (argv[remaining], O_RDONLY);
 143
 144       if (fd == -1)
 145         error (EXIT_FAILURE, errno, _("cannot open input file"));
 146     }
 147
 148   /* Read the first 4-byte word.  It contains the information about
 149      the word size and the endianness.  */
 150   uint32_t word;
 151   read_exactly (fd, &word, sizeof (word), true);
 152
 153   /* Check whether we have to swap the byte order.  */
 154   int must_swap = (word & 0x0fffffff) == bswap_32 (0xdeb00000);
 155   if (must_swap)
 156     word = bswap_32 (word);
 157
 158   /* We have two loops, one for 32 bit pointers, one for 64 bit pointers.  */
 159   if (word == 0xdeb00004)
 160     {
 161       uint32_t ptrs[2];
 162
 163       while (1)
 164         {
 165           if (!read_exactly (fd, ptrs, sizeof (ptrs), false))
 166             break;
 167
 168           printf ("this = %#010" PRIx32 ", caller = %#010" PRIx32 "\n",
 169                   must_swap ? bswap_32 (ptrs[0]) : ptrs[0],
 170                   must_swap ? bswap_32 (ptrs[1]) : ptrs[1]);
 171         }
 172     }
 173   else if (word == 0xdeb00008)
 174     {
 175       uint64_t ptrs[2];
 176
 177       while (1)
 178         {
 179           if (!read_exactly (fd, ptrs, sizeof (ptrs), false))
 180             break;
 181
 182           printf ("this = %#018" PRIx64 ", caller = %#018" PRIx64 "\n",
 183                   must_swap ? bswap_64 (ptrs[0]) : ptrs[0],
 184                   must_swap ? bswap_64 (ptrs[1]) : ptrs[1]);
 185         }
 186     }
 187   else
 188     /* This should not happen.  */
 189     error (EXIT_FAILURE, 0, _("invalid pointer size"));
 190
 191   /* Clean up.  */
 192   close (fd);
 193
 194   return 0;
 195 }
 196
 197 static error_t
 198 parse_opt (int key, char *arg, struct argp_state *state)
 199 {
 200   switch (key)
 201     {
 202     case 'u':
 203       setbuf (stdout, NULL);
 204       break;
 205     default:
 206       return ARGP_ERR_UNKNOWN;
 207     }
 208   return 0;
 209 }
 210
 211 static char *
 212 more_help (int key, const char *text, void *input)
 213 {
 214   char *tp = NULL;
 215   switch (key)
 216     {
 217     case ARGP_KEY_HELP_EXTRA:
 218       /* We print some extra information.  */
 219       if (asprintf (&tp, gettext ("\
 220 For bug reporting instructions, please see:\n\
 221 %s.\n"), REPORT_BUGS_TO) < 0)
 222         return NULL;
 223       return tp;
 224     default:
 225       break;
 226     }
 227   return (char *) text;
 228 }
 229
 230 /* Print the version information.  */
 231 static void
 232 print_version (FILE *stream, struct argp_state *state)
 233 {
 234   fprintf (stream, "pcprofiledump %s%s\n", PKGVERSION, VERSION);
 235   fprintf (stream, gettext ("\
 236 Copyright (C) %s Free Software Foundation, Inc.\n\
 237 This is free software; see the source for copying conditions.  There is NO\n\
 238 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
 239 "), "2024");
 240   fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
 241 }